Annular resistors for application in diesel electric locomotive dynamic braking systems have been known heretofore. For example, W. R. Luy, U.S. Pat. No. 4,051,452, issued Sept. 22, 1977, and assigned to the assignee of this invention, discloses an annular resistor of that type. While that resistor could be useful for its intended purposes, this invention relates to improvements thereover.